.page-about {
  --about-line: rgba(92, 107, 112, 0.26);
  --about-line-strong: rgba(11, 52, 70, 0.16);
  --about-rail: 34px;
  --about-note-w: 0px;
  background: var(--paper);
  color: var(--ink);
  padding-bottom: clamp(32px, 5vw, 0px);
  overflow-x: hidden;
}

/* ---------- 面包屑 ---------- */
.page-about .about-topbar {
  background: var(--paper);
  padding-top: clamp(16px, 2.4vw, 28px);
}

.page-about .about-topbar .breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 0.8125rem;
  color: var(--rock);
}

.page-about .about-topbar .breadcrumbs__item {
  display: inline-flex;
  align-items: center;
}

.page-about .about-topbar .breadcrumbs__item + .breadcrumbs__item::before {
  content: "/";
  margin: 0 8px;
  color: rgba(92, 107, 112, 0.55);
}

.page-about .about-topbar .breadcrumbs__link {
  color: var(--lake);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--t) var(--ease), color var(--t) var(--ease);
}

.page-about .about-topbar .breadcrumbs__link:hover,
.page-about .about-topbar .breadcrumbs__link:focus-visible {
  border-bottom-color: var(--orange);
  color: var(--blue-900);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: linear-gradient(158deg, var(--blue-900) 0%, var(--blue-800) 46%, var(--lake) 100%);
  color: var(--paper);
  padding-block: clamp(28px, 4.6vw, 62px) clamp(40px, 6vw, 92px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(90deg, rgba(245, 249, 250, 0.07) 1px, transparent 1px),
    linear-gradient(180deg, rgba(245, 249, 250, 0.07) 1px, transparent 1px);
  background-size: 56px 56px;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 52px;
  background: var(--paper);
  clip-path: polygon(0 100%, 100% 34%, 100% 100%);
  pointer-events: none;
}

.page-about .about-hero > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(30px, 4.6vw, 60px);
  align-items: end;
}

.page-about .about-hero__kicker {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  margin: 0 0 18px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--yellow);
  text-transform: uppercase;
}

.page-about .about-hero__kicker-num {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--orange);
}

.page-about .about-hero__title {
  margin: 0 0 20px;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(2rem, 6.2vw, 4.2rem);
  line-height: 1.04;
  letter-spacing: -0.03em;
  color: var(--white);
}

.page-about .about-hero__lede {
  max-width: 34em;
  margin: 0 0 28px;
  font-size: clamp(0.98rem, 1.5vw, 1.125rem);
  line-height: 1.82;
  color: rgba(245, 249, 250, 0.86);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-hero .btn--ghost {
  color: var(--paper);
  border-color: rgba(245, 249, 250, 0.5);
}

.page-about .about-hero .btn--ghost:hover,
.page-about .about-hero .btn--ghost:focus-visible {
  color: var(--blue-900);
  border-color: var(--orange);
}

/* 比分牌式概览 */
.page-about .about-hero__board {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  padding: 16px 18px;
  margin-bottom: 14px;
  background: rgba(7, 26, 33, 0.52);
  border-left: 4px solid var(--orange);
}

.page-about .about-hero__board-label {
  width: 100%;
  font-size: 0.6875rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(245, 249, 250, 0.66);
}

.page-about .about-hero__board-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(2.6rem, 6vw, 3.8rem);
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-hero__board-unit {
  font-size: 0.8125rem;
  color: rgba(245, 249, 250, 0.74);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: rgba(245, 249, 250, 0.22);
  border: 1px solid rgba(245, 249, 250, 0.22);
}

.page-about .about-hero__stat {
  background: rgba(11, 52, 70, 0.62);
  padding: 13px 14px;
}

.page-about .about-hero__stat dt {
  font-size: 0.6875rem;
  letter-spacing: 0.05em;
  color: rgba(245, 249, 250, 0.66);
  margin-bottom: 6px;
}

.page-about .about-hero__stat dd {
  margin: 0;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1;
  color: var(--white);
}

.page-about .about-hero__stat dd span {
  font-family: var(--font-sans);
  font-size: 0.6875rem;
  font-weight: 400;
  margin-left: 4px;
  color: rgba(245, 249, 250, 0.7);
}

/* ---------- 纵向时间刻度章节 ---------- */
.page-about .about-track {
  background: var(--paper);
  background-image:
    linear-gradient(90deg, rgba(92, 107, 112, 0.09) 1px, transparent 1px),
    linear-gradient(180deg, rgba(92, 107, 112, 0.09) 1px, transparent 1px);
  background-size: 72px 72px;
}

.page-about .about-track__inner {
  padding-block: clamp(6px, 1.6vw, 16px) clamp(24px, 4vw, 48px);
}

.page-about .about-chapter {
  position: relative;
  display: grid;
  grid-template-columns: var(--about-rail) minmax(0, 1fr);
  column-gap: 16px;
  padding-block: clamp(32px, 5vw, 60px);
  border-top: 1px solid var(--about-line);
}

.page-about .about-chapter:first-child {
  border-top: 0;
}

.page-about .about-chapter__rail {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  padding-top: 6px;
}

.page-about .about-chapter__rail::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 1px;
  transform: translateX(-50%);
  background: var(--about-line);
}

.page-about .about-chapter__tick {
  position: relative;
  z-index: 1;
  width: 11px;
  height: 11px;
  background: var(--paper);
  border: 2px solid var(--blue-900);
  transform: rotate(45deg);
  transition: border-color var(--t) var(--ease), background var(--t) var(--ease);
}

.page-about .about-chapter:hover .about-chapter__tick {
  border-color: var(--orange);
}

.page-about .about-chapter__index {
  display: none;
}

.page-about .about-chapter__body {
  min-width: 0;
}

.page-about .about-chapter__eyebrow {
  display: inline-block;
  margin: 0 0 12px;
  padding-bottom: 4px;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  color: var(--lake);
  border-bottom: 2px solid var(--orange);
}

.page-about .about-chapter__body h2 {
  margin: 0 0 18px;
  font-size: clamp(1.42rem, 3.4vw, 2.15rem);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: -0.015em;
  color: var(--blue-900);
}

.page-about .about-chapter__body p {
  max-width: 38em;
  margin: 0 0 16px;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ink);
}

/* 右侧边注 */
.page-about .about-chapter__note {
  margin-top: 22px;
  padding: 16px 18px;
  background: var(--white);
  border-top: 3px solid var(--lake);
  border-left: 1px solid var(--about-line-strong);
  border-right: 1px solid var(--about-line-strong);
  border-bottom: 1px solid var(--about-line-strong);
}

.page-about .about-note__num {
  display: inline-block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(2rem, 5vw, 2.9rem);
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-note__unit {
  display: inline-block;
  margin-left: 6px;
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--rock);
}

.page-about .about-chapter__note p {
  margin: 10px 0 0;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--rock);
}

/* ---------- 插图 ---------- */
.page-about .about-figure {
  margin: 26px 0 0;
  padding: 8px;
  background: var(--white);
  border: 1px solid var(--about-line-strong);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .about-figure figcaption {
  padding: 10px 4px 2px;
  font-size: 0.8125rem;
  line-height: 1.65;
  color: var(--rock);
}

/* ---------- 团队职能 ---------- */
.page-about .crew {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  border-top: 1px solid var(--about-line-strong);
}

.page-about .crew__item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  column-gap: 14px;
  padding: 15px 10px 15px 0;
  border-bottom: 1px solid var(--about-line);
  transition: background var(--t) var(--ease), box-shadow var(--t) var(--ease);
}

.page-about .crew__item:hover,
.page-about .crew__item:focus-within {
  background: rgba(245, 249, 250, 0.9);
  box-shadow: inset 3px 0 0 var(--orange);
}

.page-about .crew__num {
  grid-row: span 4;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.6rem;
  font-weight: 700;
  line-height: 1.1;
  color: var(--lake);
  transition: color var(--t) var(--ease);
}

.page-about .crew__item:hover .crew__num {
  color: var(--orange);
}

.page-about .crew__role {
  font-size: 1rem;
  font-weight: 700;
  color: var(--blue-900);
  line-height: 1.4;
}

.page-about .crew__desc {
  margin-top: 4px;
  font-size: 0.9375rem;
  line-height: 1.72;
  color: var(--ink);
}

.page-about .crew__pair {
  margin-top: 6px;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.04em;
  color: var(--rock);
  transition: color var(--t) var(--ease);
}

.page-about .crew__item:hover .crew__pair {
  color: var(--lake);
}

/* ---------- 版本阶梯 ---------- */
.page-about .versions {
  list-style: none;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin: 28px 0 0;
  padding: 0;
}

.page-about .version {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 16px 18px;
  background: var(--white);
  border: 1px solid var(--about-line-strong);
  border-top: 3px solid var(--blue-900);
  transition: border-color var(--t) var(--ease), transform var(--t) var(--ease);
}

.page-about .version:hover {
  border-top-color: var(--orange);
  transform: translateY(-3px);
}

.page-about .version--current {
  border-top-color: var(--orange);
  background: linear-gradient(180deg, rgba(255, 106, 43, 0.07), var(--white) 62%);
}

.page-about .version__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.75rem;
  font-weight: 700;
  line-height: 1;
  color: var(--blue-900);
}

.page-about .version--current .version__num {
  color: var(--orange);
}

.page-about .version__year {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.12em;
  color: var(--rock);
}

.page-about .version__name {
  margin-top: 6px;
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--ink);
}

.page-about .version__desc {
  margin-top: 2px;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--rock);
}

/* ---------- 底部导航 ---------- */
.page-about .about-outro {
  position: relative;
  background: var(--blue-900);
  color: var(--paper);
  padding-block: clamp(34px, 5vw, 62px);
  margin-top: clamp(24px, 4vw, 44px);
}

.page-about .about-outro::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 4px;
  background: linear-gradient(
    90deg,
    var(--orange) 0%,
    var(--yellow) 25%,
    var(--green) 50%,
    var(--lake) 74%,
    var(--red) 100%
  );
}

.page-about .about-outro__title {
  margin: 0 0 22px;
  font-size: clamp(1.25rem, 2.6vw, 1.75rem);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-outro__links {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .about-outro__link {
  display: block;
  padding: 16px 18px;
  background: rgba(7, 26, 33, 0.44);
  border-left: 3px solid var(--lake);
  color: var(--paper);
  text-decoration: none;
  transition: border-color var(--t) var(--ease), background var(--t) var(--ease);
}

.page-about .about-outro__link:hover,
.page-about .about-outro__link:focus-visible {
  border-left-color: var(--orange);
  background: rgba(7, 26, 33, 0.72);
}

.page-about .about-outro__link-title {
  display: block;
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-outro__link-desc {
  display: block;
  margin-top: 4px;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: rgba(245, 249, 250, 0.72);
}

/* ---------- 中等屏幕 ---------- */
@media (min-width: 640px) {
  .page-about .about-outro__links {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-outro__link {
    height: 100%;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about {
    --about-rail: 68px;
  }

  .page-about .about-track {
    background-size: 88px 88px;
  }

  .page-about .about-chapter {
    grid-template-columns: var(--about-rail) minmax(0, 1fr) 208px;
    column-gap: 34px;
    padding-block: clamp(44px, 4.6vw, 68px);
  }

  .page-about .about-chapter__index {
    display: block;
    position: relative;
    z-index: 1;
    padding: 3px 4px;
    background: var(--paper);
    font-family: var(--font-mono);
    font-variant-numeric: tabular-nums;
    font-size: 0.75rem;
    letter-spacing: 0.08em;
    color: var(--rock);
  }

  .page-about .about-chapter__body p {
    font-size: 1.0625rem;
  }

  .page-about .about-chapter__note {
    margin-top: 0;
    align-self: start;
    position: sticky;
    top: 32px;
  }

  .page-about .crew__item {
    grid-template-columns: 56px 150px minmax(0, 1fr);
    column-gap: 20px;
    align-items: start;
    padding-right: 14px;
  }

  .page-about .crew__num {
    grid-row: span 3;
    font-size: 1.9rem;
  }

  .page-about .crew__pair {
    grid-column: 3;
  }

  .page-about .versions {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
    align-items: start;
  }

  .page-about .version:nth-child(1) {
    margin-top: 42px;
  }

  .page-about .version:nth-child(2) {
    margin-top: 28px;
  }

  .page-about .version:nth-child(3) {
    margin-top: 14px;
  }

  .page-about .version:nth-child(4) {
    margin-top: 0;
  }
}

@media (min-width: 1180px) {
  .page-about .about-chapter {
    grid-template-columns: var(--about-rail) minmax(0, 1fr) 236px;
    column-gap: 44px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .version:hover,
  .page-about .about-outro__link:hover {
    transform: none;
  }
}
<<<END>>>